1. Field of the Invention
The present invention relates to a quick-connect coupling for connecting a gas supply line to a gas appliance.
2. Description of the Related Art
For connecting a gas line to a gas appliance, it is well known to provide a nipple connected to the appliance and, on an end of the gas supply line a socket member connected through a gas control valve to the gas supply line. The nipple can be coupled to the socket member for connecting the appliance to the gas line, a sleeve being slidable along the exterior of the socket member between a locking position, in which the sleeve causes the nipple to be secured in the socket member, and a released position, in which the nipple is free to move from or into the socket member.
As a precaution, it is also well known to provide the gas control valve with a control knob having a cam-like projection which, on rotation of the control knob into a valve-closed position, allows the sleeve to be moved from its locking position but, on rotation of the control knob into a valve-open position, moves into the path of movement of the sleeve so as to retain the sleeve in its locked position and thereby to prevent the nipple from being coupled with or uncoupled from the socket member. This prevents the escape of gas from the appliance when the gas line is being connected by the nipple to the socket member or disconnected by removal of the nipple from the socket member.
This prior arrangement of the control knob has the disadvantage that the cam-like member is necessarily relatively bulky and projects laterally from the gas valve when the control knob is moved into the valve closed position.
Other safety arrangements have been proposed for retaining the sleeve in its locked position while the valve is open, but these have been relatively complicated and, therefore, expensive.